The invention relates to a driving system for auxiliary equipment.
In such generally known systems, which are inter alia used in buses, lorries and in the mostly somewhat larger passenger cars, the driving of auxiliary equipment, such as the dynamo, the fan, the power steering pump, the air compressor for e.g. the brakes, the air suspension, the cabin suspension, the airconditioning compressor, the water pump, and the lubricating oil pump takes place by means of V-belts ropes or gearwheels which are driven by the crankshaft of an engine.
With such known driving systems the number of revolutions of the shaft with which the auxiliary equipment is driven will vary along with the engine speed, as a result of which, when the engine speed is low, there will be the problem that a number of components of the auxiliary equipment, such as e.g. the power steering pump or the air compressor, get critically close to their minimally allowable performance limit, or even get below this limit in the long run, unless said components, at the expense of a larger power input, or a reduced compactness, are specially designed to cope with this. Conversely, a high number of revolutions creates the problem of the auxiliary equipment delivering a higher performance than necessary, as a result of which energy and fuel are wasted at the expense of a reduced net available engine power for driving the vehicle. It is noted hereby that the amount of power wasted may be considerable, given the fact that the maximum power drawn by auxiliary equipment varies between about 15 KW and 40 KW, whereby it should be considered that 40 KW corresponds with the maximum power produced by a 1300 cc petrol engine of an average passenger car.